For much of the season the Reds have played the role of chasers in the title race, behind Manchester City. But fortunes have changed for both sides in recent weeks with United taking over pole position and moving to within just two wins of reclaiming the championship crown.
Sir Bobby has been hugely impressed by the team's recovery since the 6-1 derby defeat back in October and he has paid tribute to Sir Alex's ability to inspire his players since that awful day.
"So much credit has to go to Alex and his coaches for having United involved in the title race again this season," explained Sir Bobby in his United Review column.
"At the start of every campaign you want to avoid injuries and suspensions, and United have had such incredible misfortune with injuries that it's really staggering to be in the position we're in.
"There's been so much said about Alex - especially this season, with him passing his 25th anniversary with the club - that it's hard to add anything new. He's just marvellous, and the way he lifts everyone around him is incredible.
"The best example of that is in the reaction to City's 6-1 win at Old Trafford earlier this season. It shocked everybody associated with the club and it's certainly something you hope will never happen again.
"There's a part of you that would like to set the record straight with a similar win one day. But to come back from that result so strongly speaks volumes for how influential he is."